Passive millimeter-wave imaging provides the capability to image through dust, fog, smoke, clothing and other obscurants during daytime/nighttime operation. One approach to imaging with millimeter waves is achieved by scanning a detector assembly or radiometer with respect to a scene of interest in order to build up an image point by point. Image resolution is typically substantially less than that achievable with visible imaging systems due to the much longer wavelength of operation. In addition, important features of many scenes often exhibit low contrast, and are not readily apparent in millimeter wave imaging.